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Experimental & Molecular Medicine Mar 2023Vascular calcification is a serious complication of hyperphosphatemia that causes cardiovascular morbidity and mortality. Previous studies have reported that...
Vascular calcification is a serious complication of hyperphosphatemia that causes cardiovascular morbidity and mortality. Previous studies have reported that plasmalemmal phosphate (Pi) transporters, such as PiT-1/2, mediate depolarization, Ca influx, oxidative stress, and calcific changes in vascular smooth muscle cells (VSMCs). However, the pathogenic mechanism of mitochondrial Pi uptake in vascular calcification associated with hyperphosphatemia has not been elucidated. We demonstrated that the phosphate carrier (PiC) is the dominant mitochondrial Pi transporter responsible for high Pi-induced superoxide generation, osteogenic gene upregulation, and calcific changes in primary VSMCs isolated from rat aortas. Notably, acute incubation with high Pi markedly increased the protein abundance of PiC via ERK1/2- and mTOR-dependent translational upregulation. Genetic suppression of PiC prevented Pi-induced ERK1/2 activation, superoxide production, osteogenic differentiation, and vascular calcification of VSMCs in vitro and aortic rings ex vivo. Pharmacological inhibition of mitochondrial Pi transport using butyl malonate (BMA) or mersalyl abolished all pathologic changes involved in high Pi-induced vascular calcification. BMA or mersalyl also effectively prevented osteogenic gene upregulation and calcification of aortas from 5/6 subtotal nephrectomized mice fed a high-Pi diet. Our results suggest that mitochondrial Pi uptake via PiC is a critical molecular mechanism mediating mitochondrial superoxide generation and pathogenic calcific changes, which could be a novel therapeutic target for treating vascular calcification associated with hyperphosphatemia.
Topics: Rats; Mice; Animals; Hyperphosphatemia; Cells, Cultured; Superoxides; Osteogenesis; Mersalyl; Phosphates; Vascular Calcification; Phosphate Transport Proteins; Myocytes, Smooth Muscle
PubMed: 36854772
DOI: 10.1038/s12276-023-00950-0 -
The Biochemical Journal Mar 19691. The organic mercurial sodium mersalyl, formaldehyde, dicyclohexylcarbodiimide and tributyltin each blocked respiratory-chain-linked ATP synthesis in rat liver...
1. The organic mercurial sodium mersalyl, formaldehyde, dicyclohexylcarbodiimide and tributyltin each blocked respiratory-chain-linked ATP synthesis in rat liver mitochondria. 2. Mersalyl and formaldehyde also blocked a number of other processes dependent on the entry of inorganic phosphate into mitochondria, including mitochondrial respiration and swelling stimulated by cations and phosphate, the substrate-level phosphorylation reaction of the citric acid cycle, and swelling in ammonium phosphate. 3. Dicyclohexylcarbodi-imide and tributyltin did not inhibit the entry of phosphate into mitochondria. 4. Mersalyl and formaldehyde had a relatively slight effect on succinate oxidation and swelling stimulated by cations when phosphate was replaced by acetate, on succinate oxidation stimulated by uncoupling agents, and on swelling in solutions of ammonium salts other than phosphate or arsenate. 5. Formaldehyde blocked the oxidation of NAD-linked substrates in mitochondria treated with 2,4-dinitrophenol and the ATP-dependent reduction of NAD by succinate catalysed by ox heart submitochondrial particles. Both these effects appear to be due to an inhibition by formaldehyde of the NAD-flavin region of the respiratory chain. 6. Concentrations of dicyclohexylcarbodiimide or tributyltin sufficient to abolish ADP-stimulated respiration blocked the dinitrophenol-stimulated adenosine triphosphatase activity, whereas mersalyl and formaldehyde caused only partial inhibition of ATP hydrolysis. 7. When mitochondria were incubated with dinitrophenol and ATP, less than 10% of the total inorganic phosphate liberated was recovered in the mitochondria and no swelling occurred. In the presence of mersalyl or formaldehyde at least 80% of the total inorganic phosphate liberated was retained in the mitochondria and extensive swelling was observed. This swelling was inhibited by oligomycin but not by antimycin or rotenone. 8. The addition of mersalyl to mitochondria swollen by treatment with valinomycin, K(+) and phosphate blocked the contraction induced by dinitrophenol and caused an increase in the phosphate content of the mitochondria, but had no effect on the contraction of mitochondria when phosphate was replaced by acetate. 9. It is concluded that mitochondria contain a phosphate-transporter system, which catalyses the movement of phosphate in either direction across the mitochondrial membrane, and that this system is inactivated by organic mercurials and by formaldehyde. Evidence is presented that the phosphate-transporter system is situated in the inner membrane of rat liver mitochondria and is also present in other types of mammalian mitochondria.
Topics: Acetates; Animals; Biological Transport, Active; Depression, Chemical; Formaldehyde; In Vitro Techniques; Membranes; Mitochondria, Liver; Organomercury Compounds; Oxygen Consumption; Phosphates; Rats
PubMed: 5783467
DOI: 10.1042/bj1110665 -
BioMed Research International 2022One of the globally common cancers is colorectal cancer (CRC). At present, a surgical approach remains a good option for CRC patients; however, 20% of surgically treated...
One of the globally common cancers is colorectal cancer (CRC). At present, a surgical approach remains a good option for CRC patients; however, 20% of surgically treated CRC patients experience metastasis. Currently, even the first-line used drug, oxaliplatin, remains inadequate for treating metastatic CRC, and its side effect of neurotoxicity is a major problem when treating CRC. The Gene Omnibus GSE42387 database contains gene expression profiles of parental and oxaliplatin-resistant LoVo cell lines. Differentially expressed genes (DEGs) between parental and oxaliplatin-resistance LoVo cells, protein-protein interactions (PPIs), and a pathway analysis were determined to identify overall biological changes by an online DAVID bioinformatics analysis. The ability of DEGs to predict overall survival (OS) and disease-free survival (DFS) was validated by the SPSS 22.0, using liver metastasis CRC patient samples of GSE41258. The bioinformatics web tools of the GEPIA, the Human Protein Atlas, WebGestalt, and TIMER platforms were used. In total, 218 DEGs were identified, among which 105 were downregulated and 113 were upregulated. After mapping the PPI networks and pathways, 60 DEGs were identified as hub genes (with high degrees). Six genes (, , , , , and ) were involved with malaria, PPAR signaling, and the adipocytokine signaling pathway. High expressions of and were associated with the poor survival of CRC patients in the GSE41258 database. We predicted specific micro (mi)RNAs that targeted the 3' untranslated region (UTR) of by using miRWalk. It was found that three miRNAs, viz., miR-7-5p, miR-20a-3p, and miR-636, may be upstream targets of those genes. High expression levels of miR-7-5p, miR-20a-3p, and miR-636 were associated with poor OS of CRC patients, and the small-molecule compound, mersalyl, is a promising drug for treating oxaliplatin-resistant CRC. In conclusion, miR-7-5p miR-20a-3p, and miR-636 targeted the PCK1 biomarker in the PPAR signaling pathway, which is involved in oxaliplatin-resistant CRC. Meanwhile, mersalyl was identified as a potential drug for overcoming oxaliplatin resistance in CRC. Our findings may provide novel directions and strategies for CRC therapies.
Topics: 3' Untranslated Regions; Adipokines; Biomarkers; Colonic Neoplasms; Colorectal Neoplasms; Gene Expression Regulation, Neoplastic; Humans; Mersalyl; MicroRNAs; Oxaliplatin; Peroxisome Proliferator-Activated Receptors; Signal Transduction
PubMed: 36193307
DOI: 10.1155/2022/3825760 -
The Biochemical Journal Jul 19741. The mechanism of sulphite and sulphate permeation into rat liver mitochondria was investigated. 2. Extramitochondrial sulphite and sulphate elicit efflux of...
1. The mechanism of sulphite and sulphate permeation into rat liver mitochondria was investigated. 2. Extramitochondrial sulphite and sulphate elicit efflux of intramitochondrial phosphate, malate, succinate and malonate. The sulphate-dependent effluxes and the sulphite-dependent efflux of dicarboxylate anions are inhibited by butylmalonate, phenylsuccinate and mersalyl. Inhibition of the phosphate efflux produced by sulphite is caused by mersalyl alone and by N-ethylmaleimide and butylmalonate when present together. 3. External sulphite and sulphate cause efflux of intramitochondrial sulphate, and this is inhibited by butylmalonate, phenylsuccinate and mersalyl. 4. External sulphite and sulphate do not cause efflux of oxoglutarate or citrate. 5. Mitochondria swell when suspended in an iso-osmotic solution of ammonium sulphite; this is not inhibited by N-ethylmaleimide or mersalyl. 6. Low concentrations of sulphite, but not sulphate, produce mitochondrial swelling in iso-osmotic solutions of ammonium malate, succinate, malonate, sulphate, or phosphate in the presence of N-ethylmaleimide. 7. It is concluded that both sulphite and sulphate may be transported by the dicarboxylate carrier of rat liver mitochondria and also that sulphite may permeate by an additional mechanism; the latter may involve the permeation of sulphurous acid or SO(2) or an exchange of the sulphite anion for hydroxyl ion(s).
Topics: Ammonium Sulfate; Animals; Biological Transport; Citrates; Ethylmaleimide; In Vitro Techniques; Ion Exchange; Ketoglutaric Acids; Malates; Malonates; Mitochondria, Liver; Organomercury Compounds; Phosphates; Protons; Quaternary Ammonium Compounds; Rats; Succinates; Sulfates; Sulfites
PubMed: 4441366
DOI: 10.1042/bj1420127 -
The Journal of Physiology Mar 19981. Luminal membrane vesicles (LMV) were isolated from human and pig colonic tissues. They were characterized in terms of purity and ability to transport [14C]butyrate....
1. Luminal membrane vesicles (LMV) were isolated from human and pig colonic tissues. They were characterized in terms of purity and ability to transport [14C]butyrate. 2. The activity of cysteine-sensitive alkaline phosphatase, and the abundance of villin, NHE2 and NHE3 proteins, markers of the colonic luminal membrane, were significantly enriched in the LMV compared with the original cellular homogenate. The LMV were free from contamination by other cellular organelles and basolateral membranes, as revealed by the negligible presence of either specific marker enzyme activity or characteristic immunogenic protein. 3. The transport of butyrate into the luminal membrane vesicles was enhanced 5-fold at pH 5.5 compared with pH 8.0. Butyrate transport was temperature dependent, and was stimulated in the presence of an outward-directed anion gradient in the order of butyrate > bicarbonate > propionate > chloride. Kinetic analysis of increasing substrate concentration showed saturation kinetics with an apparent Km value of 14.8 +/- 3.6 mM and a Vmax of 54 +/- 14 nmol min-1 (mg protein)-1. 4. Butyrate transport was significantly reduced in the presence of short chain fatty acids (SCFA), acetate, propionate and other monocarboxylates (pyruvate and L-lactate). Butyrate uptake was inhibited by several cysteine group modifying reagents such as p-chloromercuribenzosulphonic acid (pCMBS), p-chloromercuribenzoate (pCMB), mersalyl acid and HgCl2, but not by the stilbene anion exchange inhibitors, 4,4'-diisothiocyanostilbene-2,2'-disulphonate (DIDS) and 4,4'-dinitrostilbene-2,2'-disulphonate (SITS). 5. The described properties of butyrate transport across the luminal pole of the colon suggest the involvement of a carrier protein, in the form of a pH-activated anion exchange process. The transporter is distinct from the erythrocyte band-3 type anion exchanger and may belong to the monocarboxylate-type transport proteins (MCT1).
Topics: Animals; Biological Transport; Biomarkers; Butyrates; Butyric Acid; Carrier Proteins; Cell Membrane; Colon; Humans; Intestinal Absorption; Intestinal Mucosa; Kinetics; Microfilament Proteins; Organelles; Sodium-Hydrogen Exchanger 3; Sodium-Hydrogen Exchangers; Swine
PubMed: 9508842
DOI: 10.1111/j.1469-7793.1998.819bs.x -
The Journal of Biological Chemistry Nov 1976Mersalyl inhibited the respiration of heart mitochondria under conditions that required the transport of (-)-carnitine and acyl(-)-carnitines. The exchange of external...
Mersalyl inhibited the respiration of heart mitochondria under conditions that required the transport of (-)-carnitine and acyl(-)-carnitines. The exchange of external carnitine and acylcarnitines for intramitochondrial carnitine was also inhibited by mersalyl and 1 mM mersalyl proved suitable for the inhibitor-stop assay of carnitine acylcarnitine translocase. The carnitine-carnitine and (-)-carnitine-acetyl(-)-carnitine exchanges involved a mole to mole exchange. The carnitine-carnitine exchange did not require energy. The carnitine acylcarnitine translocase resembles the Pi transport system in inhibition by mersalyl and N-ethylmaleimide and in lack of a cation requirement for activity; yet the two are not identical inasmuch as operation of only the former transport system was inhibited by long chain acyl(+)-carnitines. Additional results render it improbable that the transport of carnitine and acylcarnitines is catalyzed by any other known mitochondrial transport systems. The carnitine acylcarnitine translocase activity is unlikely to be shared by one of the carnitine acyltransferases because the mersalyl inhibition of carnitine palmitoyltransferase and carnitine acetyltransferase was noncompetitivcase. Rapid acetylation of intramitocondrial free (-)-carnitine occurred when acetyl-CoA was generated intramitochondrially but not with exogenous acetyl-CoA. Theese observations substantiate the view (Pande, S. V. (1975) Proc. Natl. Acad. Sci. U.S.A. 72, 883-887) that a system exists in mitochondria for the transport of carnitine and its esters and that the matrix has a pool of carnitine compounds which has access to that carnitine acyltransferase which is localized on the inner side of the inner mitochondrial membrane.
Topics: Acetyltransferases; Animals; Biological Transport, Active; Carnitine; Dithiothreitol; Kinetics; Malonates; Membrane Transport Proteins; Mersalyl; Mitochondria, Muscle; Myocardium; Rats
PubMed: 977593
DOI: No ID Found -
Antimicrobial Agents and Chemotherapy Sep 1975Mersalyl (Salyrgan), an organic mercurial diuretic, was tested against human and animal viruses with in vivo model infections in mice and tissue culture systems....
Mersalyl (Salyrgan), an organic mercurial diuretic, was tested against human and animal viruses with in vivo model infections in mice and tissue culture systems. Mersalyl was active against coxsackieviruses A21 and B1 in mice if administered intraperitoneally immediately after infection. No effect was observed if intraperitoneal treatment was delayed 1 or 2 h postinfection, or if treatment was administered either subcutaneously or per os. Topical treatment with a 5% aqueous solution of mersalyl produced a statistically significant effect against herpes simplex dermatitis in mice but the substance was inactive against systemic infections in mice with herpes simplex as well as Columbia SK, influenza, Semliki Forest, and Sendai viruses. Contact inactivation of coxsackieviruses A21 and B1 and herpes simplex virus was observed, but mersalyl was inactive in tissue culture against coxackieviruses A21 and B1, herpes simplex, influenza, rhinovirus, Semliki Forest, Sendai, and vaccinia viruses.
Topics: Animals; Antiviral Agents; Cells, Cultured; Haplorhini; Macaca mulatta; Mersalyl; Mice; Organomercury Compounds; Virus Diseases
PubMed: 810082
DOI: 10.1128/AAC.8.3.295 -
British Journal of Pharmacology and... Sep 1946
Topics: Animals; Bronchodilator Agents; Diuresis; Kidney; Mercury; Mercury Compounds; Mersalyl; Rats; Sodium Acetate; Theophylline
PubMed: 19108088
DOI: 10.1111/j.1476-5381.1946.tb00038.x -
Biochimica Et Biophysica Acta Jul 1997The matrix free magnesium ion concentration, [Mg2+]m, estimated using the fluorescent probe furaptra, averaged 0.67 mM in 15 preparations of beef heart mitochondria...
The matrix free magnesium ion concentration, [Mg2+]m, estimated using the fluorescent probe furaptra, averaged 0.67 mM in 15 preparations of beef heart mitochondria containing an average of 21 nmol total Mg2+ per mg protein. [Mg2+]m was compared with total Mg2+ during respiration-dependent uptake and efflux of Mg2+ and during osmotic swelling. In the absence of external Pi these mitochondria contain about 32 nmol/mg non-diffusible Mg-binding sites with an apparent Kd of 0.34 mM. [Mg2+]m depends on both the size of the total Mg2+ pool and the ability of matrix anions to provide Mg-ligands. Pi interacts strongly with Mg2+ to decrease [Mg2+]m and, in the absence of external Mg2+, promotes respiration-dependent Mg2+ efflux and a decrease in [Mg2+]m to very low levels. The uptake of Pi by respiring mitochondria converts delta pH to membrane potential (delta psi) and provides additional Mg-binding sites. This permits large accumulations of Mg2+ and Pi with little change in [Mg2+]m. Nigericin also converts delta pH to delta psi in respiring mitochondria and induces a large and rapid increase in both total Mg2+ and [Mg2+]m. Mersalyl increases the permeability of the mitochondrial membrane to cations and this also induces a marked increase in both total Mg2+ and [Mg2+]m. These results suggest that mitochondria take up Mg2+ by electrophoretic flux through membrane leak pathways, rather than via a specific Mg2+ transporter. Mitochondria swollen by respiration dependent uptake of potassium phosphate show decreased [Mg2+]m, whereas those swollen to the same extent in potassium acetate do not. This suggests that [Mg2+]m is well-buffered during osmotic volume changes unless there is also a change in ligand availability.
Topics: Animals; Binding Sites; Biological Transport; Cattle; Cell Respiration; Enzyme Inhibitors; Fluorescent Dyes; Fura-2; Ionophores; Magnesium; Mersalyl; Mitochondria, Heart; Mitochondrial Swelling; Nigericin; Phosphates; Spectrometry, Fluorescence
PubMed: 9230923
DOI: 10.1016/s0005-2728(97)00036-4 -
Proceedings of the National Academy of... Oct 1978This paper describes the properties and a possible biological role of a transport process across the inner membrane of rat liver mitochondria resulting in the exchange...
This paper describes the properties and a possible biological role of a transport process across the inner membrane of rat liver mitochondria resulting in the exchange of ATP(4-) (out) for ADP(3-) (in) + 0.5 phosphate(2-) (in). This transmembrane exchange reaction, designated as the ATP-ADP-phosphate exchange, is specific for the ligands shown, electroneutral, insensitive to N-ethylmaleimide or mersalyl, inhibited by atractyloside, and appears to occur only in the direction as written. It is thus distinct from the well-known phosphate-hydroxide and phosphate-dicarboxylate exchange systems, which are inhibited by mersalyl, and from the ATP-ADP exchanger, which does not transport phosphate. During ATP hydrolysis by mitochondria, half of the phosphate formed from ATP passes from the matrix to the medium by the mersalyl-insensitive ATP-ADP-phosphate exchange and the other half by the well-known mersalyl-sensitive phosphate-hydroxide exchange. These and other considerations have led to a hypothesis for the pathway and stoichiometry of ATP-dependent reverse electron transport, characterized by a requirement of 1.33 molecules of ATP per pair of electrons reversed and by the utilization of a different membrane transport pathway for phosphate and adenine nucleotides than is taken in forward electron flow and oxidative phosphorylation. The possible occurrence of independent pathways for ATP-forming forward electron flow and ATP-consuming reverse electron flow is consonant with the fact that the opposing degradative and synthetic pathways in the central routes of cell metabolism generally have different pathways that are independently regulated.
Topics: Adenine Nucleotides; Adenosine Diphosphate; Adenosine Triphosphate; Animals; Biological Transport; Electron Transport; Hydrolysis; Intracellular Membranes; Male; Mitochondria, Liver; Oligomycins; Phosphates; Rats
PubMed: 283393
DOI: 10.1073/pnas.75.10.4788